Certain called PSTN numbers ring, no answer (ISDN PRI)

Hi

We have a site in Japan using ISDN PRI (T1) - 4000 series router. Most outgoing calls work just fine, but we discovered a few toll free numbers that just ring and never answer. The local users say they can call these numbers from their mobile phone and it works (some kind of recording should be there after it answers.

I did a few ISDN Q931 debugs to toll free numbers that work fine and to the numbers that don't work. You can see the differences below. For the number that just rings and never answers, it looks like we don't get an 'alerting' message and of course no 'connect' message.

Have you ever seen this before (either in Japan or elsewhere with ISDN PRI)?

Re: Certain called PSTN numbers ring, no answer (ISDN PRI)

Thanks. I just tried that (goes under the serial interface) but I get the same result (just ringing sound but no alerting/connect message and call never really finishes answering).

We already asked to have the vendor come out and do some traces with the phone company so the phone company can tell us what they see/don't like about that call. Our primary contact won't be available much this week due to a family emergency so we may need to wait a bit to resolve this. I also wanted to have the vendor connect the T1 back to the old Avaya since that system is still there and up (we just switched over to Cisco last week at that location). I'm curious if these calls worked on Avaya. I assume they did, but would like to confirm that too.

Re: Certain called PSTN numbers ring, no answer (ISDN PRI)

You mean like the 'type of number' and 'plan' for the called number? If so, I've tried various combinations of settings for that hoping it was something simple but so far nothing afftects it. We may ultimately have to wait for our vendor to work with the telco so they can tell us what they don't like about these calls. So far it's only two numbers we know of that can't be called.

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